1. Field of Invention
The present invention relates generally to pressure washer apparatus, and more particularly, to methods and apparatus for separating and containing higher and lower-density contaminants from contaminated washing fluids for use in the pressure washing system.
2. Description of the Relevant Art
Contamination of the environment by man-made substances has been considered a serious world-wide problem. Recently, concern about contamination of earth, air, and groundwater by oil, toxic chemicals, and other hazardous wastes has expanded beyond large-scale industry to encompass the activities of many small businesses including automobile service stations, and many others. Both government regulations and social outcry have placed tremendous pressure on these businesses to avoid discharging hazardous wastes into the environment in the course of ordinary business activities.
Many businesses partake in activities which are likely to produce waste which may be harmful to the environment. For example, in an automobile service station, washing or steam-cleaning auto parts, e.g., an automobile engine, often causes engine oil, gasoline, and other chemicals to enter a storm drain system, or other waterways, thereby leading to the potential contamination of groundwater. In addition, those who service remotely located equipment generally have a need to wash the equipment without discharging hazardous waste into the environment. By way of example, persons who service roof-mounted air conditioners that contain lubricating petrochemicals, trapped pollutants, or other chemicals are not permitted to wash the equipment in a manner that could cause chemicals to run off the roof and into the surrounding environment.
To address these concerns, portable, closed-loop pressure washing equipment has become widely available which may recover oil, chemicals, and other hazardous materials from an object which is being washed. These pressure wash assemblies may efficiently recirculate, heat, and repeatedly filter a washing agent to minimize the quantity of waste material produced during a washing process. Typical of such systems are disclosed in U.S. Pat. Nos.: 5,673,715; 5,785,067 and 5,803,982, incorporated herein by reference.
These zero-discharge, closed-loop wash apparatus typically deploy a multi-step contaminant removal process designed to independently separate the heavier weight or higher density contaminants, relative the density of the washing fluid, as well as separate the lighter weight or lower density contaminants from the washing agent A collection basin of the wash apparatus, for example, may be configured to remove the heavier weight contaminants through the application of filtration baskets or through sediment settling of the coarser heavier sediments along the bottom of the collection basin. The medium weight or medium density contaminants, on the other hand, may remain suspended in the washing fluid, where they may be removed by filtration through micron filters or the like. In some designs, a succession of micron filters may be used to remove successively smaller particulates and molecules from the washing agent.
Typically, these portable pressure washing systems include a load bearing support mechanism which supports the object designated for cleaning above the collection basin. Often, these support mechanism include a porous grate device which enables the run-off wash fluids to flow easily therethrough directly into the collection below. While this grate material has adequate strength for small to medium weight objects, such a surface cannot be utilized for larger and heavier objects designated for cleaning, such as large earth moving vehicles. In this instance the support mechanism requires substantially solid metallic plate members sufficiently thick to carrying the bulk weight object.
While these solid surfaces provided excellent weight bearing properties, silting from the run-off wash fluid often occurs, especially when larger, coarser particulates or large volumes of contaminants are initially highly abundant. This collective silt build-up is problematic in that it often requires extensive manual cleanup or a prolonged cleanup time after the equipment has been washed. Accordingly, it would be desirable eliminate silting on these large support surfaces.
The present invention relates to a closed-loop pressure washing system having a pressure washer device to pressure wash an object having a contaminant, and for recovering the contaminant. The pressure washing system includes a supporting mechanism arranged to support the object while a washing fluid is flowed over the object to remove the contaminant. A collection arrangement is included at least partially located below the supporting mechanism. The collection arrangement is further arranged to receive raw run-off fluid from the support mechanism. A flush assembly is arranged to at least periodically impinge rinsing fluid onto the supporting mechanism to hydro-dynamically entrain or sweep contaminants collecting on the support mechanism into the collection arrangement.
The flush assembly is configured to preferably provide a continuous spray of the rinsing fluid along at least one side of the support mechanism toward the collection arrangement. The flush assembly also preferably includes an elongated dispensing member having a plurality of spaced-apart slits positioned along the one side, and arranged to generate and direct the spray of rinsing fluid toward the collection arrangement.
In one embodiment, the support mechanism includes a sloped top support surface to gravity flow the raw run-off fluid toward the collection arrangement. This is preferably provided by a top support surface which includes a lower side portion and an upper side portion, each extending from one end to an opposite end of the support surface. The collection arrangement includes a collection trough positioned substantially adjacent at least a portion of the lower side portion of the support surface for gravity flow collection of the raw run-off fluid therein. In this arrangement, the dispensing member is preferably positioned substantially adjacent at least a portion of the upper side portion of the support surface to provide a continuous or intermittent spray of rinsing fluid therealong toward the lower side portion.
In another aspect of the present invention, a separation assembly is provided for use with a closed-loop pressure washing system to separate contaminants from raw run-off fluid. The pressure washing system includes a pressure washing device arranged to deliver pressurized washing fluid and a collection arrangement to collect raw run-off fluid therein. The separation assembly includes a separation tank defining a storage cavity for storing reusable rinsing fluid therein. A delivery device includes a delivery port oriented to eject the raw run-off fluid into the storage cavity in a manner causing the reusable rinsing fluid therein to impart a rotational flow sufficient to enable centrifugal forces to assist in the separation of the contaminants out of the raw run-off fluid.
In one configuration, the separation tank includes a substantially cylindrical interior wall to define an upright substantially cylindrical storage cavity. The delivery device then extends into the storage cavity. The device is further arranged to eject the raw run-off fluid from the delivery port at a position or positions spaced-apart from and at an angle generally perpendicular to a longitudinal axis of rotation of the cylindrical storage cavity to impart the rotational flow.
In yet another embodiment, an intake device is included having an intake port positioned in the interior of storage cavity to draw rinsing fluid from the reusable rinsing fluid therein. The intake port is preferably positioned to draw the reusable rinsing fluid from proximate the longitudinal axis near the upper portion of the storage cavity.
The storage cavity preferably includes a conical-shaped bottom portion adapted to collect the separated contaminants from the raw run-off fluid. A valve assembly is in flow communication with the conical bottom portion to enable venting of the collected contaminants therethrough.
In another aspect, a method of contaminant separation and contaminant flushing is provided.